Motivation#

I like working with thin cotton yarns. I don’t particularly like buying new yarns when I know I’ve got clothes I can scrap for their materials. I’ve seen folks on youtube unravelling thriftshop sweaters to harvest fancy wool yarns. I wanted to see if I could do a similar process for the thin cotton yarn in my socks.

Why scrap instead of repair?#

I prefer reparing my clothes when they have holes, but some repairs will tend to interfere with comfort. For darning socks, if the repair is on the ball or sides of my foot, I’ve never succeeded in achieving the original level of comfort. The particular socks I’m used to wearing have very tiny machine knitting, which makes the repairs even more difficult. One thing that doesn’t get more difficult with those tiny knit stitches is unraveling.

What’s the economics of this?#

Terrible. It’s more work than hand-spinning raw cotton and the quality is likely to be worse. However, I don’t grow cotton, but I want the satisfaction of making a useful material and to gain the skills and appreciation for what goes into it. Also, I’m almost completely eliminating the waste from throwing out socks.

How does this compare to other cotton recycling?#

Due to the labour involved in unravelling knits, most cotton recycling just shreds and pulls apart the fibres, which tends to dramatically reduce the staple length and makes for a much weaker yarn. When I unravel and re-spin sock yarns, they’re at least as strong as the yarns that went into the socks.

The Socks#

Kirkland athletic mens socks - mostly cotton. Very cheap

Unravelling#

The sock ankles are knitted with a compound interlocked knit, consisting of the following:

  • two cotton yarns interlocking their ribbing stitches
  • a thin cord of spandex
  • a bundle of polyester fibres providing a stretch limit to the spandex

The spandex cords are pretty unwieldy while pulling out the knitting, since they’ll tend to cling to things and interfere with the layers separating in the interlock. I remove the spandex from the entire ankle before unravelling the knits. The ribbing pattern on the ankles allows access to bare spandex cords once the polyester has been cut. Then, I can use a seam ripper to cut the spandex down the entire ankle and pull it all out from the opposite side. I save these cords since it’s a useful material.

The polyester is cut to free the spandex, but has a lot of friction and I don’t bother trying to pull it free. Instead, as I unravel the cotton stitches, the polyester strands are freed and I can lift them out of the way and discard them. They are quite strong and lightweight, but as a plastic, I’d rather it be safely disposed of. Have made use of some of these strands for tying things together, but it’s not particularly pleasant to work with – it’ll cut into your skin if you pull it taught.

Re-spinning#

The unravelled yarns have a loose z-twist to them. I usually want strong double-ply yarns, so I first reinforce the z-twist with my e-spinner. The yarns could be left in their loose z-spin if the extra strength isn’t needed.

Once some extra z-twist is added and I’ve got a couple bobbins of this yarn, I can set my spinner to do s-twist and ply those yarns together.

The resulting yarn#

What I end up with is a doubled yarn, lace-weight, about 3900 yards per pound, 45 degree twist angle. I get about 15 grams of this yarn for each sock ankle.